Waste Water Treatment Plant

Value The Droplet

Waste Water Treatment Plant

Wastewater treatment is a process used to convert wastewater into an effluent that can be either returned to the water cycle with minimal environmental issues or reused. The latter is called water reclamation and implies avoidance of disposal by using of treated wastewater effluent for various purposes. Treatment means removing impurities from water being treated; and some methods of treatment are applicable to both water and wastewater. The physical infrastructure used for wastewater treatment is called a "Wastewater Treatment Plant" (WWTP).

By-products from wastewater treatment plants, such as screenings, grit and sewage sludge may also be treated in a wastewater treatment plant. If the wastewater is predominantly from municipal sources (households and small industries) it is called sewage and its treatment is called sewage treatment. The treatment of wastewater belongs to the overarching field of Public Works - Environmental, with the management of human waste, solid waste, sewage treatment, storm water (drainage) management, and water treatment.

De Hydration of Solid waste

Our Technologies

Membrane Bio Reactor

MBR stand for Membrane Bio Reactor, it is essentially a filtration process which used bio-membrane to treat wastewater. When a microfiltration or ultra filtration membrane is submerged in mixed liquor, and a positive (by gravity) or suction pressure is applied, the pores of the membrane and the resulting bio film formation on the surface of the membrane acts as a physical barrier that allow only the permeate or clean water to pass through.
Pre-treated, screened influent enters the membrane bioreactor, where biodegradation takes place.

The mixed liquor from the bioreactor is withdrawn and pumped along submerged or semi cross-flow filtration membrane modules. Permeate form the membrane constitutes the treated effluent. The reject stream, consisting of concentrated bio- solids, is returned to the bioreactor. Excess bio-solids are wasted from the bioreactor or from the return line.
One of the biggest advantages that MBR brings to the table is the relatively smaller foot print, making it ideal for a country like India.

Also, while expansion of capacity with a conventional treatment plant can mean installing another large clarifier, in an MBR plant you can simply add more membranes to existing basins expanding capacity without expanding footprint, this makes it even more pertinent for the growing economic like India and China, which are witnessing strong growth in population, urbanization and industrialization. Some other advantages that MBR offers over conventional

The 1st STP of this capacity in India to be equipped with odourcontrol units for odour free ambience in the surrounding

Low sludge production and no chemical sludge

Another aspect of MBR which it very attractive for the small industries are commercial complexes and gated colonies due to its ease of operation. This is the least appreciated aspect of this technology, but can make a great difference in the operating costs required to run the plant.

Some reason why MBR can be called an install and forget technology is :-

Eliminating phase separation (sludge settling) from the process greatly reduces the operator oversight required to keep the system running efficiently because

Most operators of activated sludge facilities will tell you they spend the majority of their time focused on the settling characteristics of the sludge at their plant

There are many factors that impact settling characteristics and these can change from one day to the next. This requires time spent in the la analyzing sludge samples, but also subsequent adjustment to the plant to maintain good settling characteristics

Although MBR being an advanced technology compared to its peers, it comes with a few disadvantages

The membrane “dry out” due to the flexible polymers leaching out, the closing/plugging of the pores, and the membranes becoming somewhat hard or brittle

In most cases the MBR technology is stated as an option of replacing the secondary clarifier. These clarifiers are operated with a single, very low HP motor, usually less than 2HP the electrical cist for this simple motor is significantly less than the filtrate pumps, chemical feed pumps, compressors, etc

Fouling is troublesome and its prevention is costly. Two thirds of the chemical and energy costs in an MBR facility are directly attributable to reducing membrane fouling

Operating costs for MBR systems are typically higher than those for comparable conventional systems. This is because of the higher energy costs if air scouring is used to reduce membrane fouling

The amount of air needed for the scouring has been reported to be twice that needed to maintain aeration in a conventional activated sludge

Higher operating costs are often partially offset by the lower cost for sludge disposal associated with running at longer sludge residence time and with membrane thickening / dewatering of wasted sludge

The treatment facility comprises the following:

Inlet works

Grit removal and screening

Biological treatment

Membrane treatment

Sludge handling

Electrical and control system

Odour control system

Ozone is “active oxygen” nature’s special element and a beautiful gift to mankind. Ozone is a triatomic allotrope of oxygen formed by recombination of oxygen atoms. It is a colourless gas with characteristic pungent pungent odor and can easily be detected at low level of 0.02ppm. it is a very strong oxidant and is over 3000 times more powerful disinfectant than chlorine. Ozone is a one –stop solution to most of the water treatment related problems such as bacteria, virus, algae, fungi, color, odor, COD and BOD. it disinfects, oxidizes, deodorized and decolorized. Ozone is generated by an electrical discharge through dry air or pure oxygen and is generated onsite because it decomposes to elemental oxygen in a short amount of time.

Benefits of Ozone

Ozone is 51%more powerful on bacterial call walls than chlorine.

Ozone kills bacteria 3000 times faster than chlorine.

Ozone is the most powerful broad spectrum microbiological control agent available.

Ozone eliminates the use of hot water and conventional sanitizer.

Ozone virtually eliminates all chemical usage.

Ozone is chemical-free, it produces NO toxic by-products.

Ozone has full FDA-approval for direct-food contact application

Ozone is clean and environment-friendly, its only by –product is oxygen.

Ozone is extremely effective as a disinfectant at relatively low concentrations.

Ozone is much safer for employees than any conventional chemical.

Ozone extends the shelf life of food products.

Ozone permits recycling of wastewater.

Ozone reduces TOC, COD & BOD from the water

TREATMENT PROCESS

The wastewater from car wash center will be first send to a bar screen chamber where large floating materials are removed. The screenings will be removed periodically for the smooth functioning of the plant. There after the Sullage enters into collection tank Thesullage stream also enters the oil separator tank for further treatment. The floating oil can be removed and collected in a separate tank and the sludge will go to sludge holding tank . The flow from the oil separator will be send to a chemical mixing cum settling tank where chemicals (Coagulants) are dosed to neutralize any toxic chemicals like surfactants and will be coagulated and settled in the primary settling tank. The overflow from the settling tank is stored in an intermediate storage tank. From storage tank it is pumped through PSF and ACF and disinfected with hypochlorite (3%) after ACF. The treated effluent will be stored in a treated water storage tank. The quality of treated water will meet the KSPCB standards and is fit for reuse such as Vehicle washing, gardening etc and it can also be safely discharged out.

Advantages:

The treated effluent water can be used for gardening and underbody wash of vehicle.

Conservation of energy.

Minimum maintenance.

Less direct labour.

Low capital and maintenance cost with effluent quality within the acceptable limits of Pollution Control Board.

Make a clean environment.

TREATMENT PROCESS

The wastewater from, bathrooms, Laundry (sullage) will be first send to a bar screen chamber where large floating materials are removed. The screenings will be removed periodically for the smooth functioning of the plant. There after the Sullage enters into collection tank then in tochemical mixing cum settling tank where chemicals (Coagulants) are dosed to neutralize any toxic chemicals like surfactants and will be coagulated and settled in the primary settling tank. The clear water is Pumped to the Activated sludge Process (Aeration Tank) for further treatment.

The overflow from the settling tank enters the Aeration Tank where the aerobic bacteria will metabolize the remaining organic matter (BOD) to harmless carbon dioxide and water. The sullage stream also enters the Aeration tank for further treatment. Air will be admitted with blowers and membrane diffusers. About 95 % BOD reduction will be achieved in this reactor. The overflow from the Aerobic reactor will be send to a Settling Tank where the sludge is – separated and recycled to the aeration tank for the proper maintenance of bacterial concentration. The overflow from the settling tank is stored in an intermediate storage tank. From storage tank it is pumped through PSF and ACF and disinfected with hypochlorite (3%) before ACF. The treated effluent will be stored in a treated water storage tank. The quality of treated water will meet the KSPCB standards and is fit for reuse such as toilet flushing, Vehicle washing, gardening etc and it can also be safely discharged out.